Citrix HDX Flash Redirection on Dell Wyse Z10D Devices running ThinOS

Whenever I spend an extraordinary amount of time troubleshooting something that should be very simple in theory, I am compelled to write something about it in order to save some poor soul the time and frustration from going through what I went through to get to the finish line.

With that said, one of my most recent struggles was getting Flash redirection working on the 7.6.300 (7.6 FP3) Citrix VDA on Dell’s Wyse ThinOS v8.2_017HF. I’m going to break this out into a couple areas where configuration is needed:

1. Wyse Device Manager:

I’m going to start by making a big assumption here that you already have the WDM (Wyse Device Manager) side setup. The requirements for that are making sure you’re on a ThinOS version that supports Flash Redirection (believe version 8.2 and above) and also have the flash redirection package (FR.i386.pkg)** in the WNOS\pkg\ folder. If you go to the ‘Packages’ tab on an endpoint in the ‘System Tools’ dialog box, it should look like this:

The other requirements on the WDM side is just making sure your WNOS.ini file has the proper configuration in place:

Also – if you like a visual confirmation that redirection is taking place (without having to right-click and confirm the context menu), use the following commands below. This will place a flashing ‘HW’ in the top left of a redirected video.

‘MMRConfig=VIDEO flashingHW=1′

**One important note with the FR.i386.pkg is to make sure you validate that it’s actually being loaded on the endpoint by going into the configuration and looking at the packages tab. This caught me at first because I didn’t have the proper MIME types associated with .pkg files in IIS. Feel free tocomment if you want me to elaborate on this one.

2. ThinClient Endpoint:

There isn’t much to configure here because the configuration of the thin client’s is obviously driven by WDM. However, I did want to include a step for this, because one of the very important factors for flash redirection to occur is the endpoint itself being able to access the content you’re redirecting (this is the very nature of the flash redirection). So both the VDA (your VDI desktop) and the endpoint itself would have to be able to access the content independently of each other. As of 05/2016 one of the limitations of flash redirection is ThinOS’s inability to support an environment that uses a proxy to get out to the internet (this is supposed to be resolved in a release for Q3 of this year)*. The summary/important message here is, make sure that the content you are redirecting can be accessed directly from the thin client as well. For my particular use case, we had to put in a firewall rule to allow the specific ports/IPs outgoing access directly, bypassing our proxy.

3. VDA Configuration (Your VDI desktop):

This is really where the major headache came into place. There was a change that was made by Citrix in the 7.6.300 VDA that changed the placement of some of these keys. This change was not documented anywhere and was only determined after escalating through the proper channels at Citrix. Dell Wyse engineering team wasn’t even aware of the change in the 7.6.300 VDAs either. I was able to work collectively with them and passed the information over to their support engineers as well – hopefully documentation/administration guides will be updated shortly. The only reason I was able to figure that the issue was in the difference in VDA versions, is because my environment contains a mixture of a small # of 7.6.0.5026 VDAs (7.6 base VDA) and a majority of 7.6.300 VDAs. Luckily enough, the 7.6.0.5026 version happened to be on some of my fellow IT colleagues PCs and I was able to notice the difference right away.

All that said, in order for flash redirection to work on your VDA, you need the following registry keys in place:

*Note – I may have an additional key in here or so, but I haven’t spent the time necessary to isolate all the keys to see what the precise set of keys are. If I do find the time, I will update this post.

4. Citrix XenDesktop Policy:

However you apply your policies, whether through Citrix Studio or Microsoft Group Policy, make sure you check to confirm that ‘Flash Acceleration’ is indeed enabled. It is enabled by default, but just make sure it wasn’t turned off and there are no explicit blacklists in for the sites you’re troubleshooting for some reason or another.

Some other thoughts:

Flash redirection in general, is quite a bit unpredictable and may introduce other issues into Internet Explorer performance. That said, be sure to know the audience you’re introducing the change to and have proper controls in place. Make sure your support teams are aware of the changes and are able to identify & communicate any changes in the user behaviors. It helps to have an awesome tight-knit helpdesk team (shout out to Vito, Rui, Connor, Ryan, Colan & Dave!). Flash redirection is most stable on Windows endpoints and behaves more erratically on Linux/ThinOS endpoints for sure.

Playback full screen video with resolution ≤ 1920 x 1200; for example, full screen playback with ThinOS resolution 1920 x 1200; in 2560 x 1600 full screen video there could be graphic issues.

After flash video is loaded it will stay in initial size; for example, resizing browser will not resize the video content; it is same behavior with Citrix HDX FR Linux client.

Only English font is supported; for example, subtitles in other languages will not be properly displayed.

In some scenario the video shows no content initially; when user resizes browser the video appears normally; it is likely to happen with x86 desktops and is a known issue for Citrix HDX FR Linux client.

Playback with videos that can work with HDX FR on Linux or Windows client: There are a number of videos/websites known as not working with Citrix HDX FR solution such as msn.com, espn.com, movies.yahoo.com, and dell.com. Flash videos simply cannot load with these websites using HDX FR solution. Some of them are working periodically; for example, videos on dell.com were working well during this Feb/March but stopped working afterwards; the results can vary depending on user location as well (US/Europe/Asia). It is therefore recommended to make sure the target videos work with HDX FR on Linux or Windows, before working with it on ThinOS.

The solution on ThinOS is based on Citrix HDX FR Linux version. It is advised to compare with Linux client in case of any issues.

Playback YouTube.com videos may run into some issues; for example, cannot show video unless user copy the URL and paste it to the browser to visit again. In case any observation we recommend to compare with Linux client.

Troubleshooting Redirection Issues:

Just a quick sentence on troubleshooting flash redirection issues; Make sure to use your logs!

Endpoint (ThinOS) Event Logs:
You’ll also be able to gain some valuable information in the event logs of the ThinOS device. Just launch the ‘System Information’ dialog and goto the ‘Event Log’ tab. Use the ThinOS dialogs to confirm that the proper INI is in place and all values configured are applying as anticipated.

With that said, I hope you guys made it this far down the post. Feel free to let me know if you hit any walls by commenting below and I’ll do my best to get back to you in a timely manner. Good luck and Godspeed!

This was tested successfully after some significant troubleshooting against vBrick’s webcasting solution.

Also, I don’t think I mentioned this in the previous post, however the most important CTX article when troubleshooting is: http://support.citrix.com/article/CTX136588 . This article contains the latest versions tested and/or known issues. In discussing with Citrix, this article is updated directly by their development team as this is being created.